Water Cooking Stability of Dried Noodles Enriched with Different Particle Size and Concentration Green Tea Powders

Functional instant noodle formulation for emergency conditions: Sensory and stability characteristics

The aim of this study was to evaluate the shelf-life and sensory characteristics of a functional instant noodle preparation designed to be used in emergencies as a tactical ration. Instant noodles were selected for their global acceptability and ease of preparation. In this study, semolina flour was used as the main ingredient, and soy protein isolate was added to increase the protein content. Additionally, green tea and beef tallow were incorporated to decrease the likelihood of oxidation. Carboxymethyl cellulose was added to increase the porosity and water absorption of the dry noodles. Spirulina powder was used as a dressing for the final product before serving to increase the nutritional value and provide the consumer with the required vitamins and minerals of the day. Physical, chemical, and organoleptic properties were assessed at multiple timepoints in a 120-day period to perform an accelerated shelf-life test by determining their critical moisture content and moisture sorption isotherm curves at 30, 45, and 55°C. The shelf-life of the product was evaluated to be 1197.28 days at 30°C and 75% relative humidity in aluminum pouches. In conclusion, the product is shelf-stable at room temperature and is recommended to be stored and used in disaster conditions such as earthquakes, floods, and wars.

Impact of pre-meal immersion on multi-scale structural changes and starch digestibility of cooked dried noodles

Pre-meal immersion is a common process for both the consumption of dried noodles and development of takeaway noodles, but its impact on the structure and digestibility of dried noodles is still unclear. In this study, dried noodles cooked for the optimal time were immersed at 80 °C for different time durations. Multi-scale structural changes, including texture, molecular structure, microstructure, and in vitro starch digestibility were studied using a combination of kinetic (first-order exponential decay function, the Peleg model, and LOS plots), physicochemical, and microscopic analysis. The relationship between multi-scale structural changes and starch digestibility was derived. As the immersion progressed, the hardness first rapidly decayed and then reached equilibrium. The decay rate in the initial stage depended on the gluten content. In most cases, the immersion process caused depolymerization of gluten proteins and further gelatinization of starch granules, which was observed from an increase in the free -SH content and decrease in the short-range ordered structure, although there were fluctuations over immersion time. Structural changes resulted in the corresponding changes in substance migration. However, a high gluten content (∼15% w/w) imparted a denser microstructure to the noodles, weakening the deterioration effects compared with a low gluten content (∼10% w/w). In vitro digestion experiments proved that samples with higher gluten content had higher starch digestion rates and lower starch digestion extent during immersion. Correlation analysis revealed that there was a negative correlation between k1 and the tightness of the gel. This study helps to reveal the structural mechanisms of starch digestibility in cooked noodles during immersion.

Effects of particle size on the structure, cooking quality and anthocyanin diffusion of purple sweet potato noodles

The effects of different particle sizes of purple sweet potato flour (PSPF) on the structure and quality of noodles and the diffusion kinetics of anthocyanins during cooking were studied. As the particle size of the PSPF decreased (from 269 to 66 μm), the adverse effects of the addition of PSPF on the quality of noodles were reduced. The smaller particle size of PSPF was beneficial for the secondary structure orderliness and the tighter microstructure of PSP noodles. The diffusion of anthocyanins in noodles to the soup during cooking could be fitted well with Fick's second law, and diffusion coefficients were in the range of 8.3248-14.0893 × 10^-9 m²/s. The noodles with 15% 66 μm PSPF showed the best cooking properties, the highest sensory score, the highest anthocyanin retention ability and a compact and orderly microstructure. Thus, they could be considered as noodles rich in anthocyanins for commercial application.

Recent Advances in the Study of Wheat Protein and Other Food Components Affecting the Gluten Network and the Properties of Noodles

Upon hydrating and mixing wheat flour, wheat protein forms a network that strongly affects the structure and physicochemical properties of dough, thus affecting the properties of noodles. Different approaches have been taken to alter the gluten network structure in order to control the dough properties. In the current review, we summarize the structure and function of wheat protein, including glutenin and gliadin, and describe food components that may affect noodle quality by interacting with wheat protein. In fact, the ratio of glutenin to gliadin is closely related to the viscosity of dough, and disulfide bonds also contribute to the gluten network formation. Meanwhile, wheat protein coexists with starch and sugar in wheat dough, and thus the nature of starch may highly influence gluten formation as well. Salts, alkali, enzymes and powdered plant food can be added during dough processing to regulate the extensional properties of wheat noodles, obtaining noodles of high quality, with improved sensory and storage properties. This review describes specific methods to reinforce the wheat protein network and provides a reference for improving noodle quality.

Gliadin interacted with tea polyphenols: potential application and action mechanism

The effect of tea polyphenols (TPs) on noodles quality was investigated, and the interaction mechanism between catechins and gliadins was explored. With TPs addition, noodles showed the significant changes in physicochemical and sensory properties. The water absorption, tensile strength and elasticity increased by 1.35%, 4.98%, 28.51% with 0.5% of TPs, and then decreased with the increasing of TPs. According to the determinations of surface hydrophobicity, spatial structure, thermal properties, amidogen and sulfhydryl content, the structure and properties of gliadin were affected by catechins. Esterified catechins tended to disrupt gliadin structures and non-esterified catechins polymerised gliadin molecules. Furthermore, molecular docking results indicated that catechins interacted with gliadin mainly by hydrogen bonds and hydrophobic action. The reactivity of catechins with gliadin was in the sequence as: epigallocatechin gallate > epicatechin gallate > epigallocatechin > epicatechin, which was based on the account of gallate and B-ring hydroxyl number discrepancy. All results suggested that catechins affected greatly on gliadin, and TPs were potentially used to improve the quality of flour products.

Effects of Tea Powder on the Cooking Properties, Antioxidative Potential and Volatile Profiles of Dried Noodles

Numerous studies indicate that tea has versatile health benefits, and attempts are being made to use it as a food additive. In this study, three types of tea powder (TP) [matcha tea powder (MTP), green tea powder (GTP), and black tea powder (BTP)] were used in noodle processing, and the cooking properties, antioxidant potential, and volatile profiles of dried tea noodles (DTN) were investigated. Between 0.5% and 2% TP addition decreased the cooking time, cooking loss, and water absorption of DTN, regardless of concentrations. TP decreased the brightness (L*) of the DTN while increasing the greenness (|−a*|) and yellowness (b*) values of matcha tea noodles (MTN) and green tea noodles (GTN), as well as the redness (a*) and yellowness (b*) values of black tea noodles (BTN). The results of the 1,1-Diphenyl-2-Picrylhydrazyl (DPPH) scavenging activity (10.84–95%), 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) free scavenging activity (2.03–92.23%), and total phenolic content (TPC) (97.32–540.97 mg/g) of the noodles increased as the TP addition increased. Besides, TP also enriched the flavor of the DTN, with alcohol, aldehydes, and ethers being the main components. In conclusion, the addition of TP positively improved the quality of the DTN and increased its antioxidative potential.

Effect of Ginkgo Biloba Powder on the Physicochemical Properties and Quality Characteristics of Wheat Dough and Fresh Wet Noodles

Effects of ginkgo biloba powder (GBP) on the chemical, physicochemical properties and quality of dough and fresh wet noodles were investigated. Lower contents of gluten and starch, and higher contents of fibre, amylose and flavonoids in GBP than wheat flour, were detected. Water absorption of dough increased and the development time and stability time of dough were decreased with GBP addition. Meanwhile, the pasting properties results showed that the addition of GBP reduced the aging degree of starch and improved the thermal stability of dough. Scanning electron microscopy results showed that addition of GBP smoothed the surface of raw noodles while increasing the hole size of the cooked noodles. With increased GBP addition (0~40%), the chewiness and extensibility of the fresh wet noodles increased significantly (p < 0.05), and the sensory scores changed, ascending from 0~20% substitution, and then descending from 20~40% substitution. The digestibility and estimated glycemic index (eGI) values of the GBP fresh wet noodles decreased significantly (p < 0.05). In general, 20% GBP addition could improve the chewiness, extensibility, taste and nutrition of fresh wet noodles, and decrease the digestibility and eGI values of noodles. Thus, GBP has potential for application in the noodle industry.

Stinging Nettle (Urtica dioica L.) as a Functional Component in Durum Wheat Pasta Production: Impact on Chemical Composition, In Vitro Glycemic Index, and Quality Properties

Stinging nettle (Urtica dioica L.) is a good source of biologically active compounds with proven beneficial health effects. This study aimed to investigate the effect of nettle herb supplementation on chemical composition, including the content of selected minerals and pigments, the in vitro glycemic response, and the cooking and sensory quality of extruded pasta. Tagliatelle-shaped pasta was produced under semi-technical scale by partial replacement of durum wheat semolina with 0, 1, 2, 3, 4, and 5% of lyophilized nettle. The partial substitution with freeze-dried nettle caused a statistically significant (p ≤ 0.05) increase in the content of minerals, especially calcium, iron, potassium, and magnesium in the products. The calcium content in the pasta fortified with 5%-addition of stinging nettle was 175.9 mg 100 g⁻¹ and this concentration was 5.8 times higher than in the control sample. At the same time, high content of chlorophylls and carotenoids (237.58 µg g⁻¹ and 13.35 µg g⁻¹, respectively) was noticed. Enriching pasta with a 0–5% addition of stinging nettle resulted in a statistically significant (p ≤ 0.05) increase in the content of the total dietary fiber (TDF) (from 5.1 g 100 g⁻¹ to 8.82 g 100 g⁻¹) and the insoluble dietary fiber (IDF) (from 2.29 g 100 g⁻¹ to 5.63 g 100 g⁻¹). The lowest hydrolysis index of starch (HI = 17.49%) and the lowest glycemic index (GI = 49.31%) were noted for the pasta enriched with 3% nettle.

The Effect of Yellow Tea Leaves Camellia sinensis on the Quality of Stored Chocolate Confectionery

Chocolate and tea leaves are considered the most valuable sources of highly bioactive polyphenols due to their potential anti-cancer properties and beneficial effects on the cardiovascular and nervous systems. The objective of the present study was the development of a sensory profiling modality that is correlated with the taste of the chocolate enriched with yellow tea phytochemicals. The additive concentration was optimized in white chocolate and the designed product was evaluated using the sensory profiling method. It was shown that the yellow tea extract in chocolate had a significant effect on the taste and color of the product. Addition of 2.0% yellow tea powdered extract increased the value of color acceptance and caused an intensification of the aromas, particularly the leafy taste, compared to the control samples. The next step of the study was to determine the influence of tea addition in white, milk and dark chocolate subjected to 6 months of storage. The designed chocolates were tested for their activity as antioxidants (DPPH, ABTS and ORAC assay) and cholinesterase inhibitors (AChE, BChE assay). It was confirmed that the yellow tea addition affected the activity of prepared chocolates with respect to radical scavenging activity and was highest for dark chocolate with yellow tea where the values were as follows: 4373 mg Tx/100 g (DPPH), 386 mg Tx/100 g (ABTS) and 4363 µM Tx/100 g (ORAC). An increase in the anti-radical activity of chocolate with yellow tea was found after 3 months of storage, but the subsequent 3 months of storage resulted in its reduction. AChE values ranged from 0.118 to 0.730 [µM eserine/g dw] and from 0.095 to 0.480 [µM eserine/g dw] for BChE assay. Total capacity to inhibit AChE and BChE differed depending on the type of chocolate and was negatively influenced by the half-year storage. Summarizing tested values for individual samples were higher, with increasing content of cocoa liquor and yellow tea extract in the product. The results of the research show that the use of yellow tea in confectionery is promising and may appoint a new direction in functional foods.